Coolant

[yARIC008]

You're supposed to use a green low silicate antifreeze then add SCAs. I use Zerex low silicate green. If I'm not mistaken DCA4 is the best as it has the molybdenum and nitrate combined which gives you the best cavitation protection. VC8 only seem so have the nitrate in it based on my last go around with it and test strips. Another important factor is the pressure the system is running at. Stock is 13 psi but some run at half that. In theory the lower pressure gives you less cavitation protection but less problems with keeping the system sealed.

 

[Kevin 007]

Yes the system pressure is an interesting one to keep in mind. Makes sense.

I do tend to run a lower pressure cap, 10psi and in some cases 7psi. I have done this for years, while maintaining SCA levels and have yet to have a problem and have torn down some wet sleeve engines that were running as low a 0 psi for years with no signs of cavitation/pitting on the liners.


But its certainly food for thought

 

[yARIC008]

I am running 7 psi now too. I had extra thick liners installed and keep scas up so hoping I’m okay. Its not a daily driver now so if she blows up again it’ll be my opportunity to take it all apart and fix alot if things.

 

[Kevin 007]

And most industrial or OTR applications run a 7-10psi cooling system and they are just fine. I think automotive applications are generally higher psi's due to the higher boiling point for the less then smart drivers that let their vehicles overheat to the point of the coolant boiling. Kind of an idiot proofing design so to speak.

As our trucks age, I feel that a lower pressure caps are a good way to reduce cooling system stress and therefore, increasing overall reliability and lowering cost of ownership/operation.